Energy needs of our society continue to grow at an increasing rate. Unfortunately, much of this energy is supplied by nonrenewable resources whose relative availability continues to decrease. Members of the power generation industry are gradually developing more efficient methods of power generation, with the ambition of one day generating their electricity from clean, sustainable renewable resources.
One such potential area for expansion is wind energy. Wind turbines of various sizes and designs can mitigate our dependence on foreign energy supplies while providing distinct benefits to our domestic economy. Wind turbine designs may be optimized for particular locations and conditions. Moreover, wind turbines use the wind, a clean, nonpolluting energy source.
The United States has tremendous wind energy resources. In California, wind farms currently replace almost 4 million barrels of oil per year. At least sixteen states have even greater wind potential than California based on measured average wind rates.
The installed wind energy generating capacity in the U.S. is currently estimated to be around 6,400 MW, and is expected to generate about 16.7 billion kWh of electricity in 2004, which is less than about 1% of the total U.S. electricity generation. By contrast, the total amount of electricity that could potentially be generated from wind in the United States has been estimated at about 11,000 billion kWh annually, over three times the electricity generated in the U.S. today.
Existing wind farms help demonstrate how wind energy can help meet growing needs for affordable, reliable power. Moreover, with continued government encouragement through, among other things, heightened technology transfer from national laboratories to the wind energy industry, wind energy is slated to become more economical than traditional fossil-fueled energy. Some estimate that wind related energy sources could provide at least six percent of the nation's electricity by 2020. More importantly, the wind generator could help revitalize farms and rural communities without consuming any natural resource or emitting any pollution or greenhouse gases.
Wind turbines have traditionally been built using a turbine attached to a horizontal axis suspended high above the ground. Wind turbines have been used for centuries to capture the power of the wind to mill grain into flour or pump water. More recently, as previously indicated, wind generators; such as a wind turbine configured to produce electricity, have also been used to supplement the electrical energy supply.
Unfortunately, while the electricity generated by wind turbines use a clean, nonpolluting energy source, traditional wind turbine systems have a somewhat unexpected negative effect on the wildlife in the immediate environment, particularly on the local avian population.
Specifically, some wind turbine systems are configured to maintain such a fast rotation that the blades become almost invisible. The wind turbines must have sharp blades that efficiently cut through the wind. Moreover, the same sharp blades are often positioned high in the air at the top of a wind tower. As the wind towers are typically the tallest structures in the area, they become a natural perch for raptors and other birds. A deadly combination when coupled with the virtual invisibility of the sharp rotating blades, which are also very good at slicing through eagles and other birds. For example, the Center for Biological Diversity reports that the approximately 5,400 turbines located around Altamont Pass in California kill more than an estimated 800 birds a year, including several species protected by federal and state laws.
Even the officially documented avian collision and electrocution incidents reported from 1985 to 1988 at various California wind energy facilities tend to support the contention that the wind generators are more dangerous to the larger birds. For example, of the 147 reported incidents during the period from 1985 to 1988, 101 were raptors, of which 34 were eagles and 58 were hawks. Some estimate that in the Altamont Pass Wind Resource Area, an average of 11 eagle and 17 hawk incidents occurred annually. Unfortunately, ninety-one percent of all documented avian incidents eventually resulted in mortality for the bird. This high mortality rate and incident information helps identify the need to better understand and resolve the biological effects of wind projects on the surrounding environment.
As such, there is clearly a need for a more environmentally friendly and efficient wind based power device. Unfortunately, none of the currently available systems can provide environmental protection for the surrounding avian population.